Let's get right to that brand-new tropical storm forecast to be a hurricane. Now on a path to impact south florida. Could disrupt the republican national convention in tampa. And sam, of course, was tracking the storm overnight. Let's look deeply into this storm. There's a lot happening in the tropics. We'll concentrate on isaac right now. Overnight, the thunderstorms in this storm allowed them to say this is a tropical storm. This will be a rough one for guadeloupe, and the dominican. Moves towards puerto rico, the line the hurricane center has lined out for us. By the time it moves over guadeloupe, it's a very powerful storm. Gets to puerto rico and a category 1 hurricane, south of the island. Then, continues in category 1 strength. You can see the string on the forecast. Through the dominican republic, haiti. And monday, right off the south coast of florida. This doesn't mean it doesn't strengthen and weaken here. It means it averages a category 1 strength. That's a sloppy, messy storm for all involved. We haven't decided where this storm goes. Look at the area of high pressure here and here. And there's where the republican convention is next week, in tampa. This storm has got to find itself being steered somewhere between these two areas of high pressure. It's likely florida, could be the gulf. We have to watch this storm system every minute. Sam, thanks very much. We'll have the latest on the gop senate candidate who stirred

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